Mathematical description of plastic behaviour in tensile tests of austenitic stainless steel AISI 310 in temperature range 293-1173 K

The predictability of the tensile mechanical behaviour was studied by the authors on the stainless steels outside the range of proportionality by the use of different phenomenological constitutive equations. Some of them, of the type σ = σ(epsilonsub(p)), where σ = true stress and epsilonsub(p) = true plastic strain, involve only one independent variable, whereas others of the type σ = σ(epsilonsub(p),epsilon), where (epsilon) = true strain rate, took into account two dependent variables. The experimental data were obtained from solution annealed AISI 310 steel samples tested at different temperatures between 293 and 1173 K and for two strain rates, 1.2.10-3 and 2.8.10-1 s-5. Analysis of the results showed the good fitting of Ludwigson's law for the equations with one independent variable only, whereas for the equations with two independent variables that of Matteazzi-Petrone-Piatti follows the experimental results very well at room temperature where the rate processes are important. (author)